University of North Florida
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Contact Info

Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Pig Feed

Classification: Agricultural -> feed -> pig

Citations 3

"Flow Injection Spectrophotometric Determination Of Copper Using Bis(cyclohexanone)oxalyldihydrazone"
Anal. Chim. Acta 1995 Volume 304, Issue 1 Pages 97-100
N. Chimpalee, D. Chimpalee, S. Srithawepoon, T. Patjarut and D. Thorburn Burns*

Abstract: A sample (250 µL) was injected into a water carrier stream (1.35 ml/min) which was then sequentially merged with streams (1.35 ml/min) of 27% citric acid solution, 37% ammonia solution and 0.18% bis(cyclohexanone)oxalyldihydrazone solution then passed through a reaction coil (4 m x 0.8 mm i.d.) to a detector cell with detection at 600 nm. The calibration graph was linear up to 20 µg/ml Cu; the detection limit was 1.3 µg/ml and RSD was 0.92% (n = 10). The method was applied to the determination of Cu in steels, copper-based alloys and pig feeds and to copper monitoring in an alkaline scale-removal process.
Copper Spectrophotometry Complexation

"Flow Injection Extraction-spectrophotometric Determination Of Copper Using Bis(acetylacetone)ethylenediimine"
Anal. Chim. Acta 1996 Volume 331, Issue 3 Pages 253-256
N. Chimpalee, D. Chimpalee, S. Lohwithee, L. Nakwatchara and D. Thorburn Burns*

Abstract: Sample (250 µL) was injected into a water carrier stream (1.4 ml/min) which was then merged sequentially with acetate buffer of pH 5 (1.4 ml/min), 0.2% bis(acetylacetone)ethylenediimine in aqueous 10% ethanol (1.4 ml/min) and CHCl3 (1 ml/min). The mixture was passed through an extraction coil (400 cm x 0.8 mm i.d.) to a phase separator. The organic phase was fed to the spectrophotometric detector where the absorbance was measured at 370 nm. The calibration graph for Cu was linear for up to 100 µg/ml, the detection liwas 0.42 µg/ml and the RSD (n = 10) for 20 µg/ml Cu was 1.95%. The method was applied to Cu-based alloys and pig feeds. The results for the alloys were in agreement with the certified values and those for pig feed were confirmed by AAS. The sampling rate was 20/h.
Copper Spectrophotometry Sample preparation Buffer Reference material Method comparison Extraction Organic phase detection Phase separator

"Sulfamethazine And Sulfathiazole Determination At Residue Levels In Swine Feeds By Reverse-phase Liquid Chromatography With Post-column Derivatization"
J. AOAC Int. 1988 Volume 71, Issue 4 Pages 710-717
Smallidge RL, Kentzer EJ, Stringham KR, Kim EH, Lehe C, Stringham RW, Mundell EC.

Abstract: The method was modified from previous work (Stringham et al., Anal. Abstr., 1983, 44, 1G18). The sample and internal standard, sulfamerazine, were extracted with 1.5% diethylamine and 0.3 M HCl in aqueous 25% methanol, and the extract was analyzed on a C18 column, e.g., LiChrosorb RP-18 (7 µm), with a guard column and acetonitrile - 2% acetic acid (17:83) or acetonitrile - methanol - 2% acetic acid (1:4:20) as mobile phase. The compounds were derivatized post-column with 0.75% 4-dimethylaminobenzaldehyde solution in anhydrous acetic acid - methanol - water (5:3:2) and the derivatives were detected at 450 nm. Calibration graphs were rectilinear from 0.4 to 25 ppm of the cited drugs in the samples, and recoveries of 0.1 to 10 ppm were 96.7 to 99.7%. The coefficient of variation (n = 6) were 13 and 2% for 0.5 and 13 ppm, respectively.
Drugs Sulfamethazine Sulfathiazole Sulfadimidine HPLC Spectrophotometry Post-column derivatization